Adjustable finger gripping means in transfer mechanisms



Feb. 19, 1957 E. B. BYAM 2,731,531

ADJUSTABLE FINGER GRIPPING MEANS IN TRANSFER MECHANISMS Filed NOV. 12, 1953 2 Sheets-Sheet l E. B. BYAM Feb. 19, 1957 ADJUSTABLE FINGER GRIPPING MEANS IN TRANSFER MECHANISMS Filed Nov. 12, 1953 2 Sheets-Sheet 2 INVENTOR ATTORNEYS ietats Erwin B. Byam, Wolcott, Conn, assignor to The Waterbury Farrel Foundry & Machine Company, Waterbury, Conn., a corporation of Connecticut Application November 12, 1953, Serial No. 391,652

Claims. (Cl. -166) This invention relates to transfer mechanism for headers or nut formers or like machines, and particularly to the construction of the finger mechanism for gripping a blank and transferring it from one work station to an adjacent work station.

In devices of this character it is usual to provide a die block or die bed provided at its face with a plurality of dies, and a gate having a plurality of punches cooperates with the dies to form the blank or workpiece progressively as it is moved successively from one die to the next. Transfer mechanism is provided to carry the work in this manner, the tranfer mechanism including transfer fingers which grip the blank at one station and carry it to the next succeeding station where the blank is released and the transfer fingers are then returned to the first station to receive a second blank. As shown, the transfer mechanism is of the general type described in the application of Joseph M. Schaefier and Erwin B. Byam, Serial No. 289,085, filed May 21, 1952, now Patent No. 2,728,267, issued December 27, 1955, the present invention relating particularly to the finger holders and fingers employed in the transfer mechanism.

It will be obvious that the opening in the transfer fingers to receive the blank must be correctly aligned with the die openings and should be capable of adjustment so that this alignment may be readily effected. It is also desirable that the opening between the transfer fingers to receive the work should be adjustable so that the opening will be of the proper size to receive the workpieces or blanks, and an arrangement should also be made for permitting the fingers to spread apart under spring tension to receive the blank and to then be urged toward each other so as to grip the blank tightly in order to carry it from one station to the next.

As illustrated, the transfer mechanism of the present invention is provided with finger holders, each comprising two legs, one of which is pivoted to the other so that the legs may spread under spring tension to receive the work. The fingers themselves are attached to the legs of the finger holder and are urged toward each other under spring pressure. Also, adjusting means are provided to adjust the opening between the fingers so that it will be of the proper size to receive the blank, and the spring pressure with which the legs of the finger holder are urged together may also be adjusted to adjust the grip upon the blank.

One object of the present invention is to provide improved transfer mechanism for transferring a blank from one station to another in a header or like machine. A further object of the invention is to provide a transfer mechanism having improved finger structure of simple design but so constructed that the opening between the gripping fingers may be readily adjusted and at the same time the spring pressure which holds the gripping fingers together may be readily adjusted.

A still further object of the invention is the provision of transfer mechanism of the character described wherein the atent 2,781,531 Patented Feb. 19, 1957 ice horizontal position of the fingers may be readily and easily adjusted by the manipulation of a single adjusting screw.

To these and other ends the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawings:

Fig. 1 is a front elevational View of a portion of a transfer mechanism provided with improved transfer fingers embodying my invention;

Fig. 2 is a side elevational view thereof;

Fig. 3 is a detail elevational view of one of the legs of the finger bar;

Fig. 4 is a similar view of the other leg of the finge bar; and

Fig. 5 is a detail perspective view of the holder for the finger bar.

To illustrate a preferred embodiment of my invention, I have shown in the drawings a header or nut former or like mechanism comprising a die bed 10 having a plurality of dies 11 at the face thereof. Supported upon the die bed are brackets 12 (only one of which is shown), these brackets carrying a shaft 13 upon which is pivotally mounted a support 14 for the carrier mechanism.

This support includes a forwardly extending dovetail 15 upon which is slidably mounted a carrier slide 16, this slide being secured in place by a gib 17. Secured at the upper end of the support 14 is a horizontally disposed rack 18, the purpose of which will be apparent as the description proceeds.

Secured upon the face of the slide 16 are a plurality of transfer finger mechanisms, only one of which is shown in the drawing. This structure comprises a block 19 held in place upon the face of the slide 16 by cap screws 20. The block 19 may be adjusted vertically by means of the adjusting screw 21 threaded into a poppet 22 on the face of the slide.

Rotatably mounted within the block 19 is a shaft 23 and mounted nonrotatably on the upper end of this shaft is a pinion 24 which is in mesh with the rack 18.

The foregoing mechanism is illustrated in the prior copending application above referred to, but it will be obvious without further explanation that, as the slide 16 is reciprocated, the engagement of the teeth of the pinion 24 with those of the rack 18 will efiect rotation of the shaft 23. As will hereinafter appear, the transfer finger mechanism is carried by the shaft 23, and upon rotation of this shaft the finger mechanism will likewise be rotated to turn the blank through an angle of degrees as it is being transferred from one die station to the next. Any suitable mechanism, such as that shown in application Serial No. 289,085, may be provided for reciprocating the slide 16.

Secured to the lower end of the shaft 23 is an L-shaped holder member 25, shown more especially in Fig. 5. This member comprises spaced lips or walls 26 and 27, these lips being provided with registering openings 28 and 29 to receive the pivot pin of the finger bar as described hereinafter. A supporting plate 30 is secured by any suitable means, such as welding, across the lower edges of the horizontal portions of the lips 26 and 27.

The finger bar comprises two separate members, oneof which is shown in Fig. 3 and-the other in Fig. 4. One of these members, as shown in Fig. 3, comprises a leg pOrtion 31 and a horizontally extending head portion 32. The latter is provided with an opening 33 to receive a pivot pin 34 passing through the openings 28 and 29 in the holder 25 so as to pivotally secure the finger bar to this holder.

Also the head 32 of this portion of the finger bar is provided with an opening or hole 35 to receive a spring 36 (Fig. l) which bears at its upper end against the upper portion of the holder 25 to urge the finger bar in a counterclockwise direction about its pivot 34. An adjusting screw 37 is mounted in the supporting plate 30 to engage the lower surface of the head 32 of the finger bar and limit its movement by the spring. It .will be appreciated that the position of the lower .end of the finger bar may be adjusted in a horizontal direction by adjustment of the screw 37 as the spring will always maintain the head of the finger bar in contact with this screw. i

The other portion of the finger bar structure comprises a second leg member 38, and at its upper end this member is provided with a rounded or partially cylindrical portion 39 designed to rest pivotal ly in .a complementally shaped opening 40 in the head 32 of the first portion of the finger bar so that these members will be pivotally connected together to swing apart in a horizontal direction as shown in Fig. 1. These two portions of the finger bar may be assembled together, and when placed between the lipsor side plates 26 and 27 of the holder 25, the leg members 31 and 38 will be held in assembled relation by these side plates.

Secured at the lower ends of the legs'31 and 38 are fingers 41 and 42 having between them an opening 43 to receive the workpiece or blank, these fingers being secured in place by screws 44 and 45. An adjusting screw 46 carrying a lock nut 47 is threaded into the leg 31 of the finger bar mechanism, this screw bearing against the end of a screw 48 secured to the finger ,bar 38 so as toadjustably limit the approaching movements of these members. That is, the adjusting screw 46 may be turned in and out to adjust the size of the opening 43.

Also a bolt 49 is passed looselyithrough the legs 31 and 38, and a spring 50 carried by this bolt exerts tension I on the legs 31 and 33 to urge them, together so as to norinally maintain the end of the screw 46 in engagement with the screw 48. The tension of the spring 50 may be adjusted by the adjusting nuts 51 so as tosecure greater or less gnip upon the blank.

From the above it will be apparent that there is provided a finger mechanism which may be readily assembled and which at the same time is so constructed that adjustment of the size of the opening and also adjustment of the grip upon the blank may be readily and easily made. Likewise, the horizontal position of the fingers may be adjusted within limits by adjustment of the finger bar structure about its pivot 34. Also the pivot member 38 will be held in assembled position within the opening 40 of the head 32 of the other finger bar by the assembly of the structure between the side walls 26 and 2? of the holder 25.

While I have shown and described a preferred embodiment of my invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the invention and within the scope of the claims. j

What I claim is:

l. A transfer mechanism for a metal-working machine having a plurality of dies, said mechanism comprising a finger holder having spaced wall members, a finger bar member pivoted thereto having a depending leg, a second leg member having an upper portion within said holder and pivoted to the first member adjacent its upper end at a point between said wall members and extending into said holder in substantially parallel and spaced relation to said first leg, gripping fingers on the lower ends of each of said legs, and means for holdingsaid finger bar member in adjusted positions about its pivot with the holder, said means comprising an arm onthe finger bar member, an I adjusting screw in the holder at one side of the'member engaging said arm and a spring at the other side thereof urging the member against said screw.

2. A transfer mechanism for a metal-working machine having a plurality of dies, said mechanism comprising a shaft, a finger holder secured thereto and provided with spaced wall members, a finger bar member having a horizontally disposed head portion pivoted between said wall members and also having a depending leg, a second leg member pivoted to said head portion within said holder at a point between the wall members and depending there from in spaced substantially parallel relation to the first leg member, a gripping finger secured to the lower end of each of the leg members, and adjustable means to urge said fingers together and to limit their approaching movement.

3. A transfer mechanism for a metal-working machine having a plurality of dies, said mechanism comprising a shaft, a finger holder secured thereto and provided with spaced wall members, a finger bar member having a horizontally disposed head portion pivoted between said wall members and also having a depending leg, a second leg member pivoted to said head portion at a point between the wall members and depending there from in spaced substantially parallel relation to the first leg member, a gripping finger secured to the lower end of each of the leg members, adjustable means to unge said fingers together and to limit their approaching movement, said head having a socket therein, and said second leg having a rounded portion rotatably received in said socket and held in place by said wall members.

4. A transfer mechanism for a metal-working machine having a plurality of dies, said mechanism comprising a shaft, a finger holder secured thereto and provided with spaced'wall members, a finger bar member having a horiz ont ally disposed head portion pivoted between said wall members and also having a depending leg, a second leg member pivoted to said head portion at a point between said wall membersand depending therefrom in spaced substantially parallel relation to thefirst leg member, la.

gripping finger secured to the lower end of each of the leg members, adjustable means to urge said fingers together and to limit their approaching movement, and cooperating means on said head portion and holder to adjust the finger bar member about its pivot.

'5. A transfer mechanism for a metal-working machine having a plurality of dies, said mechanism comprising a :shaftja finger holder secured thereto and provided with spaced wall-l members, a' finger bar member having a horizontally disposed head portion pivoted between said Wall'members and also having a depending leg, a second sleg'member piv'otedto said head portion at a point between said wall members and depending therefrom in spaced substantially parallel relation to the first leg member, a gripping finger secured to the lower end of each of the leg members, adjustable means to urge said fingers together and to limit their approaching movement, c0-

operating means on said head portion and holder to adjust the finger bar member about its pivot, said means comprising a spring on one side of said head portion and an adjusting screw at the other side thereof.

References Cited in the file of this patent UNITED STATES PATENTS Friedman Aug. ll, 1953 e; in 

